1. Technical Field
The present invention relates generally to a semiconductor device, and more particularly, to an input/output sense amplifier of a semiconductor device.
2. Related Art
FIG. 1 is a diagram illustrating the configuration of a conventional input/output sense amplifier 10.
The following description will be given with respect to the conventional input/output sense amplifier 10 with reference to FIG. 1. The conventional input/output sense amplifier 10 includes a latch unit 11, a precharge unit 12, and a data input unit 13. The latch unit 11 includes a first PMOS transistor P1 which is connected between a driving voltage VDD and a first node n1 and receives an output signal of a second node n2, a second PMOS transistor P2 which is connected between the driving voltage VDD and the second node n2 and receives an output signal of the first node n1, a first NMOS transistor N1 which is connected between the first node n1 and a third node n3 and receives the output signal of the second node n2, and a second NMOS transistor N2 which is connected between the second node n2 and a fourth node n4 and receives the output signal of the first node n1. The first node n1 is connected to a second output terminal OUTB, and the second node n2 is connected to a first output terminal OUT.
The precharge unit 12 includes a third PMOS transistor P3 which is connected between the driving voltage VDD and the first node n1 and receives a strobe signal STB, a fourth PMOS transistor P4 which is connected between the driving voltage VDD and the second node n2 and receives the strobe signal STB, and a fifth PMOS transistor P5 which is connected between the first node n1 and the second node n2 and receives the strobe signal STB.
The data input unit 13 includes a third NMOS transistor N3 which is connected between the third node n3 and a fifth node n5 and receives an output signal of a first local transmission line LIO, a fourth NMOS transistor N4 which is connected between the third node n3 and the fifth node n5 and receives an output signal of a second local transmission line LIOB, and a fifth NMOS transistor N5 which is connected between the fifth node n5 and a ground voltage VSS and receives the strobe signal STB.
The operation of the conventional input/output sense amplifier 10 is as follows. During a read operation, the strobe signal STB is enabled, and when data is input through the first and second local transmission lines LIO and LIOB, the data is amplified and transmitted to the first and second output terminals OUT and OUTB.
In the conventional input/output sense amplifier 10, a voltage drop phenomenon occurs in which the voltage of the third node n3 and fourth node n4 is lower than a precharge voltage level because of impedance caused by the transistors in the input/output sense amplifier 10. This leads to deteriorated operational characteristics of the input/output sense amplifier 10.